Creators involved in the crossover included writers Jeph Loeb, Joe Casey, Mark Schultz, Joe Kelly, Phil Jimenez, and Peter David, and artists that included Mike Wieringo, Ed McGuinness, Doug Mahnke, Ron Garney, and Leonard Kirk.

The Our Worlds at War storyline involves the heroes battling Imperiex, a cosmic entity who represents entropy and threatens to destroy the universe.

Thanks to the sacrifice of Strange Visitor and General Rock, Earth's forces crack Imperiex's armor, releasing his energy.

In a desperate gambit, Superman dives into the Sun, gaining a massive power boost.

Realizing that Warworld cannot be destroyed without releasing Imperiex and triggering another Big Bang, Superman and Martian Manhunter transport Imperiex and Brainiac back in time to the Big Bang, destroying them both.